6.4 gas exchange in the leaf of a plant Flashcards
1
Q
how is the gas exchange in plants similar to that of insects?
A
- no living cell is far from the external air
- diffusion takes place in the gas phase (air)
2
Q
plants adaptations for rapid diffusion
A
- no cell is far form a stoma(ta)-> short diffusion pathway
- numerous interconnecting air- spaces that occur throughout the mesophyll -> gases can come into contact with mesophyll cells
- large surface area of mesophyll cells-> rapid diffusion
3
Q
where are stomata?
A
mainly on the underside of leaves
4
Q
what is each stoma surrounded by?
A
a pair of guard cells
5
Q
what is so special about guard cells?
A
they can open and close stomatal pores
6
Q
draw a single diagram if a vertical section through a dicotyledonous leaf
A
page 138
7
Q
explain the advantage to a plant of being able to control the opening and closing of stomata
A
helps control water loss by transpiration
